水解对SrAl_2O_4:Eu^(2+),Dy^(3+)稳定性的影响(英文)  

EFFECT OF HYDROLYSIS ON THE STABILITY OF SrAl_(2)O_(4):Eu^(2+), Dy^(3+)

作　　者：杨志平[1] 杨勇[1] 朱胜超[1] 刘冲[1] 冯建伟[1] 

机构地区：[1]河北大学物理科学与技术学院发光与显示研究所,保定071002

出　　处：《硅酸盐学报》2004年第9期1050-1053,共4页Journal of The Chinese Ceramic Society

摘　　要：研究了SrAl2O4∶Eu2+,Dy3+长余辉材料在模拟潮湿环境条件下的稳定性。采用了2种模拟环境方法对样品进行了预处理。第1种方法为样品于室温条件下在去离子水中浸泡3d;第2种方法为样品在70℃的水中浸泡10h,或者经过人工加速老化试验制备产物。结果显示:第1种方法的预处理产物没有发生明显的分解,然而与未经处理的样品比较,发现其发光强度和发射光谱的峰值位置都发生了变化。而通过第2种预处理方法得到的产物发生了明显的分解分层。将溶液过滤蒸干得到两层的粉末状固体,分别记作上层产物和下层产物。通过X射线衍射和X射线能谱分析产物晶体结构,上层产物是Sr3Al2(OH)12,下层产物是Sr3Al2(OH)12和SrAl3O5(OH)的混合物。下层产物具有长余辉特性,为SrAl3O5(OH)∶Eu2+,Dy3+发光,发射光谱峰值位于485nm,而原样品SrAl2O4∶Eu2+,Dy3+的发射光谱峰值为520nm。实验结果表明SrAl2O4∶Eu2+,Dy3+长余辉材料在高温或潮湿条件中应用时,需要进行包膜处理。The stability of SrAl_(2)O_(4)∶ Eu^(2+),Dy^(3+) subject to pretreatment mimicking environmental effect was studied. Two types of pretreatment methods was used in the test. In the first case, the sample was soaked in water at the room temperature for 3 days and in the second case the sample was either soaked in 70 ℃water for 10 hours or subjected to accelerated aging under artificial environment. The results show that the first type pretreatment does not introduce significant decomposing. Furthermore,in comparison with the untreated sample, there are changes in both the intensity of luminescence and the peak position of the (emission) spectrum. However after second type pre-treatment the solution was observed to decompose into two layers,upper layer and bottom-layer. The solution was then filtrated and evaporated to obtain two different powder samples, referred as to upper-layer and bottom-layer powder samples thereafter. X-ray diffraction analysis and X-ray energy spectra analysis show that the upper-layer sample is Sr_(3)Al_(2)(OH)_(12) and the bottom-layer is the mixture of Sr_(3)Al_(2)(OH)_(12) and SrAl_(3)O_(5)(OH). The bottom-layer of sample shows characteristic of long afterglow corresponding to SrAl_(3)O_(5)(OH)∶Eu^(2+),Dy^(3+). The emission peak of the long afterglow is at 485nm, which is far from 520 nm of SrAl_(2)O_(4)∶ Eu^(2+), Dy^(3+). Based on these results, it shows that the SrAl_(2)O_(4)∶ Eu^(2+), Dy^(3+) phosphor needs coating processing when used at high temperature or exposed to moisture air for long times.

关 键 词：长余辉材料 光致发光 晶体结构 水浴 

分 类 号：TQ174[化学工程—陶瓷工业]